Ads
related to: firearm chamber pressure measuring equipment reviews
Search results
Results From The WOW.Com Content Network
The test cartridge must be inserted into the chamber in such a way that the hole in the test cartridge case lines up with a gas port hole that channels the gas pressure from the cartridge case to the face of the sensor. The measurement accuracy of the pressure measurements with 21st century high-pressure sensors is expected to be ≤ 2%. [7]
Within firearms, chamber pressure is the pressure exerted by a cartridge case's outside walls on the inside of a firearm's chamber when the cartridge is fired. The SI unit for chamber pressure is the megapascal (MPa), while the American SAAMI uses the pound per square inch (psi, symbol lbf/in 2) and the European CIP uses bar (1 bar is equal to 0.1 MPa).
Pressure recorded in NATO design EPVAT Barrel with Kistler 6215 Transducer, HPI GP6 Transducer or by equipment to C.I.P. requirements 9 mm (9×19mm NATO) Designed to chamber NATO ammunition: 252.0 / (36,550) 315.0 / (45,687) Pressure recorded in C.I.P. design barrel at mid-case position 12.7 mm (12.7×99mm NATO) Designed to chamber NATO ammunition
A visual inspection of the barrel is also performed. If the firearm passes these first steps, the standard proof takes place. The proof consist of firing two overloaded cartridges producing 25% more chamber pressure than the C.I.P maximum pressure limit for the same cartridge in its commercial version.
While CUP and LUP numbers were intended to be comparable to the crushing power of a given pressure, the numbers are not equivalent. Since a longer duration, lower pressure pulse can crush the cylinder as much as a shorter duration, higher pressure pulse, CUP and LUP pressures frequently register lower than actual peak pressures (as measured by a transducer) by up to 20 %.
The burning firearm propellant produces energy in the form of hot gases that raise the chamber pressure which applies a force on the base of the projectile, causing it to accelerate. The chamber pressure depends on the amount of propellant that has burned, the temperature of the gases, and the volume of the chamber.